Expedition leaders: Dr. Tristan Guttridge, Dr. Phil Matich and PhD candidate Bryan Keller

Crew: Gabby, Jason, Jen, Josh, Katy and Kennedy and Sabrina

Introduction

The first Saving the Blue trip was a huge success! We captured, tagged, and released 52 sharks of seven different species, in the course of the six-day excursion. Along the way, we saw much more than just sharks. This was an exciting and unforgettable week, with dolphins, mahi-mahi, blue holes, night fishing, and our team’s first ever tiger shark! So, what exactly does it take to Save the Blue? Read the full rundown below!

Day 1

We started off at the private charter airport at 10:00 AM to check in luggage and meet the crew. Some guests knew each other from previous excursions, so they were able to catch up and get to know the new faces in the waiting area. Everyone was able to meet both trip leaders, Dr. Tristan Guttridge and Dr. Phil Matich. We received our own Saving the Blue shirts and began to discuss our hopes for the week ahead! You could feel the excitement in the room, especially from Tristan, who had been dreaming of and planning to run a research trip to Andros for quite some time.

After weighing all the luggage and research equipment, we were on our way to the island. Some of us slept on the flight, while others chatted or simply looked out of the windows at the gorgeous blue water below. As we approached Andros, we were all able to see how truly wild it is, with most of the western side of the island protected as a national park. Blue holes pocket a landscape without a building in sight.  For many of us, this is one of the most magical features of this place: a remote mosaic of habitats where the land meets the sea, hidden from human touch.

We landed, checked in through customs, and were off to our home for the next six nights, the Andros Island Bonefish Club. After arriving, everyone quickly settled in and met for lunch in the common room.  We ate our lunches while chatting about the plan for our first outing of the week. It was decided we would start off with deploying drum lines to get the crew acquainted with this style of sampling. Drum-lining is a common technique for sampling small- to large-bodied sharks, and is used by Saving the Blue to learn more about the abundance and distribution of the shark fauna on east side of Andros.

We gathered our gear and piled into Captain Cole’s trusty boat for a few hours out on the water. It was late afternoon, roughly 3:30 PM, when we made the ten-minute ride out to the edge of the Middle Bight to start our first set of drum lines. Drum lines consist of a floating buoy tied to a rope that’s secured to a 45-pound (20-kilogram) weight, which has a monofilament line attached to it with a baited hook. The weight is dropped into the water with the rope length allowing the buoy to comfortably sit at the surface so we always know where our gear is.

Crew members were each given a task to get the process going. Some collected data, such as time, location, depth, water salinity, and levels of dissolved oxygen. Others baited the hooks, attached the monofilament line to the weights, or deployed the weights and hooks overboard once we arrived at the desired spot. Once all five lines were set, we waited an hour prior to checking to see if anything had taken the bait. Jobs were again handed out for those who wanted to pull the lines in by hand and rebait any hooks that had no shark but bait stripped away.

With the workup taking about 10 minutes, we reset the line and immediately headed back to our first line for our second round of checks. Each line on this second check had a shark at the end of it (see above the odd blotch on a reef shark we caught)! This time blood samples were taken. Blood samples are obtained by placing the shark onto its back, which puts it into tonic immobility (a relaxed trance-like state that makes it easier to handle them), and a needle and syringe are used to draw blood from the vein at the base of the caudal fin, for diet analysis. All blood and tissue samples were placed into vials labeled with the number of the PIT tag inserted into the shark, and then stored in a cooler on the boat.

With the crew overjoyed at the success of our first outing, we headed back to the lodge to get cleaned up and eat dinner. Over dinner we discussed the day, and some of our team assisted in separating the plasma from the blood using a portable centrifuge. The resulting plasma can be used to assess diet for our sharks within a four to six week time period!  

Day 2

We were up for an early morning for breakfast at 6:30 AM. The Bonefish Club does an incredible job of providing us with breakfast to-order and coffee every morning. We quickly ate, loaded up the boat, and headed out to the Middle Bight for our first full day on the water. It was a little rainy and windy, but that did nothing to stop the anticipation of what the day would bring – more sharks!

After a busy morning of drum lines and receiver collections, we headed back to the Bonefish Club for lunch. We spent about a half hour back at the lodge with some of us not even leaving the boat while we ate our packed lunches of sandwiches and chips. After lunch, we reloaded and headed to a spot a few minutes from the lodge to see what we would find. Everyone was making friendly wagers on what we would catch, some said lemon and reef sharks, while others were hopeful for something bigger, like a bull shark.

We reset our drum lines while it rained around us, and visited the boat as we waited. When it was time to check again, we’d caught a male reef shark!

We ended the day with a total of seven sharks, four nurse and three reef, as well as one barracuda. We headed back, cleaned up, ate another delicious meal provided by the club, then prepared for a lecture from Tristan. He spoke of the different species of shark and rays commonly seen in the Bahamas, including their behavior, reproductive biology, and conservation status. Everyone thoroughly enjoyed the talk, and we all headed off to bed in preparation for our third day in Andros.

Day 3

We were awake, fed, and packed up by 8:00 AM, heading out to Isla’s Spot, which is named after a rambunctious young lady who is full of energy, like the sharks that frequent its waters. This spot is known to be heavily populated with lemon sharks, appropriately named for their yellow coloration.

Upon arriving, we decided to start the day with something new. The team would get their first try at gill netting. This process involves a net with floats at the top and small weights at the bottom, set in very shallow water (<1.5m, 5ft).  The mesh on the net is set wide enough to allow a small shark’s head through but not the rest of its body. The net is set and monitored for any splashes, and checked every fifteen minutes to assure that no animals are restrained for long periods of time.

Once the net was set, half the crew stayed with Tristan on shore and the other half went back to the boat with Phil to set some drum lines in deeper channels. Within a few minutes, the gill netting team had caught their first juvenile lemon shark and begun the workup process in a large container filled with seawater. Everyone had the opportunity to use the skills they had learned on the first two days, to measure, tag, and take blood samples from the juvenile lemon sharks, under Tristan’s supervision. While the gill netting team were having luck with several juvenile lemon sharks, the drum lining team caught their own sub-adult lemon sharks.

After about an hour, the teams switched so that everyone could get a chance to try out the gill netting. Even more lemon sharks were caught and released, with a final count of eight lemon sharks in total. Three were caught on the drum lines, while five were caught in the gill net, one of those being the smallest we would capture on our trip, at just 76cm total! We packed up all our gear, and around noon and headed back to the lodge for a long break before our first night fishing adventure in a deep channel in the middle of the Bight.

Back at the lodge we napped, explored, read, or simply chatted with the crew. Around 5:30 PM we ate dinner and discussed plans for the evening. We would be setting drum lines from about 7:00 to 11:00 PM, to see if we would get different species in deeper water after dusk.

As it rained, we travelled to the sampling location, and were surprised by a few dolphins who decided to tag along. They swam with the boat as we headed to the channel, and for the remainder of daylight, they seemed to be intrigued with what we were doing, as we continuously saw their fins break the surface near us. We set our drum lines as the rain tapered off, and the water became a mirror during the last few minutes of fading light, and into a night that would produce an amazing experience.

Sampling sharks at night is inherently more challenging than during the day, but also much more exciting, as you don’t know what’s on the line until it breaches the surface and is brought alongside the boat! During our night of fishing, we captured a total of four sharks, which included two more nurse sharks and the first two blacktips of the trip. We were all excited to sample the blacktips because of their iridescent coloration, brilliantly dark and triangular shaped fins, and powerful swimming ability. With four sharks caught, this brought us to twelve sharks in total for the day. There were a few hooks missing bait, as the sharks had gotten away. The entire time we were out on the water, it was wonderfully calm, with a lightning storm all around us adding a fun and pleasantly eerie feel to the night.

We returned around 11:30 PM, and with everyone exhausted from our busy day, we all headed to bed.

Day 4

Due to our late night, we had a later breakfast at 7:30 AM, but with the weather being windy and rainy, it was decided we would stay in for the morning. Tristan and Phil both gave lectures on shark research and the different methods used to tag sharks. Phil also went into detail on how the blood and tissue samples are used to study shark diets.

Once the weather cleared, we decided to stick close to the lodge, as Tristan would have to leave for filming in Nassau by midday. We set up six drum lines in the shallow creek adjacent the lodge. Large, mature lemon sharks are resident to the creek, and we were hopeful to catch and tag some of these individuals. After setting the gear, with good humor, we watched two lemon sharks swim in the opposite direction of our baited hooks!

Two rounds of checks brought us no luck, and we headed back in to say our goodbyes to Tristan. Once he was on his way we decided to enjoy a little downtime, and went to snorkel a local blue hole nicknamed The Coffin. The mixture of warm, shallow water surrounding The Coffin and the cold water emitted from within it created a hazy thermocline akin to a translucent curtain, which obscured a clear view of deep, blue water until you swam through it. The water in the blue hole was a bit murky, and the temperature was brisk, but this didn’t stop everyone from taking full advantage of the area. We got to see a lot of beautiful corals and reef fish while we all practiced our freediving in the dark blue waters.

After about a half-hour we hopped back into the boat and got back to business. Six more drum lines were set, and we did some waiting. We were having no luck at all today, with no sharks on any line after two rounds of checks. On the third round, we decided to call it a day and started pulling in our lines after checking them. Crew members that were not pulling in the lines began packing up gear and preparing the boat to head back. But, on the second to last line, we were all happy to hear there was a shark. As it was being pulled in the first guess was that we had a reef shark, but Phil mentioned how it was much bigger than any of the others we had caught. This immediately intrigued everyone on the boat as we were hoping to get yet another species on this trip.

At first the guesses were bull shark but there was an outcry of excitement when the words tiger shark was uttered. We were not disappointed!!! The tiger shark was so big and powerful, it pulled the boat (and the crew) for a few minutes before being brought along the side of the boat with little fuss. He was calm and seemed at ease on the line as we secured him with a tail rope. The whole crew was exhilarated; especially our own Captain Cole, who contacted Tristan right away to let him know what he had missed.

We did a quick workup on him and noticed that he was missing the majority of the upper lobe of his caudal fin. The shortened caudal fin was probably the result of an old injury that had healed several years ago, but left the shark permanently altered. It was no less adept a predator though, and its body size indicated it was in very good condition. If that would have been complete he would have easily been over three meters long, a mature male tiger shark. After the workup, we let him go and he swam off strong, giving the boat a slight nudge before cruising back toward the reef.

We pulled our last line and headed back to the lodge for dinner, with everyone in high spirits. It may have been a mostly uneventful day for shark research, but having a tiger at the end made up for all the waiting.

Day 5

Silky shark morning! A day we were all looking forward to because we knew we were going to be able to get in the water with them prior to any captures. We headed out to the buoy in the Tongue of the Ocean by 8:00 AM.

Everyone quickly geared up and jumped in to the clear blue waters. Within minutes we had half a dozen sharks in the water with us, zooming in close with no regard for personal space. The group had a blast swimming with these sharks for about twenty five minutes before it was time to get out and see if we could catch one for a workup.

With the water depth at about 1000 meters, we were unable to do our typical drum lines so we had to change our process.  We used the poly ball technique, which is the same concept as drum lining, but without the weight. We set one out and drifted the boat. While we waited, we were greeted by two gorgeous mahi-mahi, which made a few quick passes around the boat.

We were able to capture four silky sharks on this morning, and surgically insert acoustic tags into two of the sharks. This process was performed by both Phil and Bryan, and assistants were able to watch them put the sharks into tonic immobility and quickly make small incisions in their abdomens in order to insert the acoustic tags. Once the tag was inserted, they stitched the incisions closed, and the sharks were released.

In addition to the acoustic tags, each silky sharks was outfitted with a PIT tag and a blue, external tag affixed to the dorsal fin, each with a unique number. Snorkeling with silkies is a favorite for everyone that joins Saving the Blue and Silent Hunter Group trips in Andros, and these external tags will allow guests to help us understand about the schooling behavior of these sharks. The external tags and their numbers are observable by snorkelers, and sharks that return to the buoy will be recorded during all future trips, to help us understand if sharks tend to form familiar groups, or aggregate with random partners.

After our extremely exciting and busy morning, we headed back closer to the island to do some more drum lining in the shallower waters of Andros’s back reefs. We set six drum lines, and while we waited, we headed to a nearby blue hole for a quick snorkel to cool off and explore the fishes and coral in the area. The water was crystal clear and we were able to see a large barracuda and gigantic crab hiding in nooks of the caves pocketing the blue hole.

The turquoise waters and surrounding deserted islands provided a picturesque setting for a busy afternoon, with six sharks in total on our lines, including a blacknose. The other five sharks included an adult lemon shark, the first of the trip! We ended the day with a total of ten sharks. Our four silky sharks from the morning, three reef, one nurse, one lemon, and the one blacknose.

We headed back for dinner, shared our footage from the morning shark dive, and then headed off to bed.

Day 6

Our last full day had arrived.

We were all up and ready for a packed day of shark captures, and no one wanted to think about the fact it would all be over tomorrow. We headed to a spot that was known for great hammerhead sightings, and were curious if we would end up catching one.

Six drum lines were set, and the waiting began, but it would not last long. Everyone by now was well acquainted with each other, and enjoyed just chatting and snacking while we waited to check the lines, but the buoys indicated a lot of activity shortly after deploying the gear, so we quickly started checking, and ended up processing more than a dozen sharks in a short period of time. Over the course of this day, at two different locations, we sampled thirteen different reef sharks in total, with a few narrowly evading us. Based on the condition of our gear, something large was taking our bait. We had a couple of hooks that were bitten through, and one hook was bent almost completely straight. In the middle of checking, we saw a very large shark swim past us, but were unable to get a closer look at it, and we did not catch it on any of our hooks.

Between sampling locations, we took a shore break at a small island to search its beaches for a satellite tag that had popped off of a two-meter silky shark that had been tagged by our team in April. We walked around the beach and the shallows for an hour or so, unsuccessful in our search, but energized for the second half of the day, which would be filled with more hard-fighting reef sharks.

When Bryan was done with his lecture and everyone was able to ask him their questions, Phil had us play a game: two truths and a lie about bull shark lifestyle. He gave us facts (and lies) from ten different categories, describing the behavior, physiology, and morphology of bull sharks. For each category, there were two true facts and non-truth. The point of the game was to figure out which statement was untrue. This was an extremely fun and a unique way to educate on bull sharks and some of his research.

To end our last night, many of us stayed up a little later than normal, having a few beers and sharing stories out under the pavilion, graced by a panorama of stars filling the skies that had been cloudy each of the previous nights. We all finally headed to bed to be well-rested for our final outing and return home.

Day 7

We returned to the Tongue of the Ocean for our last day, to spend more time in the water with the silky sharks, and to hopefully tag a few more of them.

The water was like glass, with perfect visibility. We got in the water immediately upon arrival and were surrounded by silky sharks and thimble jellyfish. It was surreal and exhilarating being in the water with both these animals, feeling no fear. Some of the same sharks returned from Day 5, but new individuals also joined us, no shyer than our previous visit.

After an hour, we reluctantly got out of the water and started working on capturing a few more sharks, to increase our sample size for future investigation of their social patterns and residency to the tongue of the ocean.

By the end of the morning we had successfully captured and completed workups on three silky sharks, two of which had acoustic tags implanted, with all three PIT, and externally tagged.

With the exciting morning over, we headed back to the lodge to pack up, eat lunch, and hang out prior to departure. When we arrived we had the unfortunate surprise that the power was out and we were unable to shower or rinse our gear. The entire group found it comical and it did nothing to dampen our spirits. We spent our time eating lunch and helping to pack up all the gear from the week.

After everything was packed and ready to go, we said our goodbyes to the wonderful staff of the Andros Island Bonefish Club. The taxi and Cole’s truck were loaded up with our belongings and we made the too-soon trip back to the airport.

Thank you

Thank you to our research trip leaders Dr. Tristan Guttridge, Dr. Phil Matich and PhD Candidate Bryan Keller for guiding the team through an incredibly successful week. A huge thank you to our seven research assistants for their passion, determination and endless enthusiasm to work hard, learn and produce results. We would also like to thank the Andros Island Bonefish Club for their hospitality, and the hardworking and ever professional Cole from PFO Charters for his top class boating and captaining skills.

Gratitude must also go to all on the trip for their generosity in allowing us to use their images in this blog.